The present invention concerns catheters, and particularly a catheter for the injection of fluid into and sealing the uterus with provision made for positioning of the uterus for examination purposes.
Current medical practice includes the injection of gas or fluid into the uterus for better definition of same and the fallopian tubes. The prior art device disclosed in U.S. Pat. No. 4,089,337 is of background interest for the reason that it may function both as an injector and enables both sealing and positioning of the uterus being examined. While the above mentioned device has proved useful some risk exists, if used without care, of contacting the uterine wall with the catheter tip. Further, in certain instances, it may lose its sealing capability.
Other catheter devices, in similarity to the above device, also utilize an inflatable member for effecting a seal within the human body. Such other devices are most commonly directed toward uses other than with the uterus. Examples of such other catheters are found in U.S. Pat. No. 2,687,131; 3,459,175; 3,766,920; 3,802,418; 3,812,841; 3,896,816; 3,948,270. U.S. Pat. No. 507,573 discloses a syringe with a stop thereon limiting syringe insertion. The above disclosures, in some instances, disclose body contacting disks, plates, etc., which limit insertion of a supporting catheter into a body cavity. U.S. Pat. No. 2,687,131 is of interest in that a "pear" shaped inflatable member is disclosed therein which is adapted for external abutment against a body part in a urethral catheter.
The above mentioned device disclosed in U.S. Pat. No. 4,089,337 utilizes a spherical inflatable member from which the catheter tip, when in place, projects toward the upper end of the uterus. Excessive catheter penetration during manipulation of the device could result in tip contact with the uterine wall. Further, the spherical shape of the inflatable member does not conform to the lower portion of the uterus interior and, hence, often forms less than a perfect seal. A spring is relied upon to seat the spherical member against the uterine wall.